97332017-09-16Nano-Particle Scandate Cathode for Space Communications Phase 2, Phase IICompletedJun 2011Nov 2013We propose an improved cathode based on our novel theory of the role of scandium oxide in enhancing emission in tungsten-impregnated cathodes. Recent results have demonstrated the efficacy of nano-particle scandium oxide, but a detailed theory on the mechanism of operation has been lacking. Our theory explains published data and points to an optimized cathode, which we propose here to build and test. The cathode is the performance-limiting component in high-frequency linear beam amplifiers such as traveling wave tubes and klystrons. The required bandwidth, data rate, number of channels, frequency, and output power are going up. The performance of linear beam amplifiers is acutely limited by current cathode performance. Scandate cathodes offer a way to increase top emission from 10 A/cm2 to at least 50 A/cm2. Phase I proved the feasibility of applying layers on unagglomerated scandium oxide on impregnated cathodes. Phase II will optimize, test, and commercialize the process. The long life (estimated 100,000 hours) of this cathode will lower system acquisition and maintenance costs in satellites and space probes, as well as terrestrial communications and radars. Higher emission current density will permit higher frequencies, more bandwidth, and more power than current art. There is a shortage in bandwidth and channels in many wireless networks. The scandate cathode provides a way out.43632435Communications, Navigation, and Orbital Debris Tracking and Characterization Systems32825.2Radio Frequency Communications36895.2.2Power-Efficient Technologies324810NanotechnologySBIR/STTRSpace Technology Mission DirectorateJet Propulsion LaboratoryJPLNASA CenterPasadenaCAAmes Research CenterARCNASA CenterMoffett FieldCAe-beam, Inc.IndustryBeavertonORGlenn Research CenterGRCNASA CenterClevelandOHGoddard Space Flight CenterGSFCNASA CenterGreenbeltMDCaliforniaMarylandOhioOregonTherese GriebelCarlos TorrezRobert A JonesGary JahnsBernard Vancil